Sonotube Calculators
Concrete Depot calculator category

Sonotube Calculators

Use these sontube calculators to plan round tube forms, pier sizes, concrete volume, cubic yards, bag counts, waste, and cost for deck footings, fence posts, columns, and small concrete tube pours.

See all calculators Other concrete calculators
πr²h cylinder volume
8″–18″ tube sizes
ASTM C94 ready-mix
5–10% waste allowance

All sontube calculator tools

Choose the sonotube calculator that matches your job. Use the general tool for tube form planning, or use the concrete sonotube calculator for concrete volume, bags, waste, and cost.

Sonotube calculator

Plan round Sonotube form size, diameter, depth, tube quantity, and basic pier layout before ordering materials.

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Concrete sonotube calculator

Estimate concrete for tube footings, including cubic yards, cubic feet, bag counts, waste, and basic material cost.

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Sonotube calculator guide

Which sonotube calculator should I use?

Choose the tool that matches the task. Use the general Sonotube calculator for tube form planning, and use the concrete Sonotube calculator when you need concrete volume, bags, waste, and cost.

Need Recommended tool Why
Tube form size and layout planning Sonotube calculator Best for checking round tube diameter, depth, quantity, and basic form planning.
Concrete volume for round tube footings Concrete sonotube calculator Uses the cylinder formula to estimate cubic feet and cubic yards from diameter and depth.
Bag count for small tube pours Concrete sonotube calculator Good for DIY pours where you need 40 lb, 60 lb, or 80 lb concrete bag counts.
Deck post, fence post, or pier prep Sonotube calculator Useful when you want to compare common tube sizes before setting posts or piers.
Ready-mix order check Concrete sonotube calculator Helps turn tube volume into order quantity with a waste allowance before the pour.

What are sonotube calculators?

Sonotube calculators help estimate round concrete tube forms used for posts, piers, deck footings, porch supports, and small columns. A tube pour is calculated as a cylinder, so the main inputs are diameter, depth, and quantity. These tools help you plan tube size, concrete volume, bag count, waste allowance, and rough cost before work starts. They are estimating tools, not structural design tools.

Common sonotube calculator use cases

Deck footings

Estimate tube form size and concrete quantity for deck posts, porch supports, and small pier footings.

Fence posts

Plan concrete tube holes for fence posts where diameter, depth, and quantity control the material need.

Round piers

Use the cylinder volume formula to estimate concrete for round piers, columns, and support bases.

Bagged concrete pours

Estimate 40 lb, 60 lb, and 80 lb bag counts for small tube pours before buying concrete bags.

Sontube calculator FAQs

How do I calculate concrete for a sonotube?
Use the cylinder formula: volume = π × radius² × depth. Convert the tube diameter into radius first. Then convert cubic feet into cubic yards by dividing by 27.
What is the difference between the sonotube calculator and the concrete sonotube calculator?
The Sonotube calculator is for general tube form planning. The concrete Sonotube calculator is focused on concrete volume, bag count, waste, and cost for tube footings.
What sonotube size should I use?
Common tube diameters include 8 inches, 10 inches, 12 inches, 16 inches, and 18 inches. The right size depends on the load, soil, frost depth, local code, and project type.
Should I add waste to a sonotube concrete estimate?
Yes. A 5% to 10% waste allowance is common for many tube pours. Use more if the holes are uneven, oversized, or hard to measure.
How many bags of concrete do I need for a sonotube?
Bag count depends on tube diameter, depth, quantity, and bag yield. Use the concrete Sonotube calculator to estimate 40 lb, 60 lb, and 80 lb bag counts.
Do sonotube footings need to go below frost depth?
In many cold areas, footings may need to extend below local frost depth. Check local code or ask a qualified contractor before digging.
Does this replace a contractor or engineer?
No. These calculators provide estimates only. Final footing size, reinforcement, embedment depth, and structural design should be checked by a qualified person.